1. Field of the Invention
This invention relates to a cover receptacle assembly of plastics for use in laboratories, in particular for the polymerase chain reaction (PCR) technique. The cover receptacle assembly is intended for small probes and may have a capacity of about 0.2 to 0.5 ml.
2. Description of Related Art
Cover receptacle assemblies of the prior art comprise a tubular receptacle and a cover connected thereto adjacent the receptacle opening by means of a flap. In a reaction receptacle of plastics as disclosed in European patent 0 149 797 B1 the flap comprising strap hinge means is integrally connected both to the receptacle and the cover. For facilitating injection molding of such assemblies the structure thereof is such that the cover normally assumes a position wherein it is laterally pivoted away from its closing position for 180.degree. and the strap hinge means extends parallel to the receptacle opening. Due to the resilience of the strap hinge means the cover remains in such an initial position or returns thereto unless it is being held in its closing position. As a result the cover receptacle assembly when being in its open condition requires a lot of space.
Quite often a great number of cover receptacle assemblies are inserted in holders to allow for the simultaneous handling of various probes, which holders have apertures arranged in parallel rows to receive the cover receptacle assemblies. Such holders may belong for example to heating or mixing devices. Furthermore, it has become known to interconnect a plurality of cover receptacle assemblies by strip portions so as to form receptacle strip assemblies in order to allow for simultaneous handling thereof even when they are not positioned in a common holder. One field of use is the polymerase chain reaction (PCR) technique wherein a temperature program is being executed in a heating device. When therein a temperature of more than 90.degree. C. has been reached, DNA is being separated into its two rods. At temperatures of about 40.degree. to 70.degree. C. copies of the DNA are being made by use of a primer. The DNA is being multiplied in a plurality of heating and cooling cycles.
When the probes are being handled simultaneously, the substantial space requirement of the open cover receptacle assemblies is particularly disadvantageous. This is so because they must be filled and unfilled when they are positioned within the holder. If laterally projecting covers overlap adjacent receptacle openings, pipetting of the probes becomes difficult and the risk of contamination thereof is enhanced. When the receptacle rows are largely spaced from each other in order to avoid this, the holders and accordingly the heating and other auxiliary devices will become volumineous and expensive.